Headlight tester



Dec. 22, 1953 J. P. CARR HEADLIGHT TESTER 7 sheets-sheet 1 Filed April l. 1950 ll. ilAt.

INVENTOR JAMES ECAIH? BY Mw'u d Dec. 22, 1953 J. P. CARR HEADLIGHT TESTER 7 Sheets-Sheet 2 Filed April l 1350 mvENToR JMES P. GARR aY #40M ATTORNEY Dec. 22, 1953 J. P. CARR 2,663,216

HEADLIGHT TESTER Filed April 1. 195o 7 sheets-sheet s A /xy l, 3%/

INVENTOR' JAMES n GARR ATTO RN EY Dec. 22, 1953 '.J. P. CARR HEADLIGHT TESTER 7 Sheets-Sheet 4 Filed April l. 1950 QN. mw. 0N.

INVENTOR JAMES P. GARR BY MMM i ATTORNEY Dec. 22, 1953 J. P. CARR 2,663,216

i HEADLIGHT TESTER Filed April 1, 195o 7 sheets-sheet 5 INVENTOR -JAMEs P. CARR ATTORNEY Dec. 22, 1953 J. P. CARR 2,663,216

HEADLIGHT TESTER Filed April l 1950 7 Sheets-Sheet 6 INVENTOR JAMES P. GARR ATTORNEY Dec. 22, 1953 J. P. CARR HEADLIGHT TESTER 7 Sheets-Sheet 7 Filed April l. 1950 INVENTOR JAMES P. GARR BY ,gf/M,J 5, /W-L ATTORNEY and a U-shaped top and end wall cover 2t.

Patented Dec. 22, 1953 ICE HEADLIGHT TESTER James P. Carr, Lansing, Mich., assignor to Food Machinery and Chemical Corporation, San Jose, Calif., a corporation of Delaware Application April 1, 1950, Serial No. 153,474

9 Claims.

This invention has to do with the testing of automobile headlights and has for its general object the provision of a simpliied and improved .headlight tester.

The manner of accomplishing the foregoing object, as well as further objects'and advantages will be made manifest in the following description taken in connection with the accompanying drawings in which:

Fig. 1 is a plan view of the headlight tester of my invention.

Fig. 2 is a sectional view of Fig. 1 taken on the line 2 2 thereof.

Fig. 3 is a phantom perspective View of the headlight'tester of my invention illustrating the manually powered reflector control mechanism.

Fig. 4 is an. enlarged face View of the reflector of the invention taken on the line 4 4 of Fig. 2.

Fig. 5 is a sectional view taken on the line 5 5 of Fig. 4. y

Fig. 6 is an enlarged sectional View taken on the line 6 6 of Fig. 1.

Fig. 7 is a front elevational View of Fig. 6.

Fig. 8 is a cross sectional View taken on the line 8 8 of Fig. 2.

Fig. 9 is a cross sectional view taken on the line 9 9 of Fig. 2.

Fig. 10 is a perspective View of the invention looking upwardly from beneath the same.

Fig. 1l is a perspective view of the invention with the vertical mounting bars thereof broken away to compress this view onto the page.

Fig. 12 is an enlarged side elevational View of the sliding tester base partiallybroken away to illustrate the construction thereof.

Fig. 13 is a plan view of an autom-obile and showing in full lines the rst position of the headlight tester when testing the headlights of said automobile, and showing subsequent positions of the tester in broken lines.

Referring specifically to the drawings, the invention is there illustrated as embodied in a headlight tester I5 which includes a housing It made up of sidewalls i'! `and i8, a bottom wall l! The sidewalls Il and i8 and cover 2l! of the housing H5 are preferably die formed from plastic.

Each of the sidewalls has apertured lugs 2l, 22, and 23 which extend inwardly from the rear edge thereof and apertured lugs Ztl and 25 which extend inwardly from upper and lower portions of the front edge thereof. Formed integral with the lugs 23 andv 25 are apertured footings 26 and 21. The sidewalls Il? and i8 are also provided at opposite points along their upper edgesr with horizontal lugs 28, vertically faced bosses 2S and horizontal lugs 3G.

Thesidewall l1 has a longer horizontal lug 3l extending inwardlyY from its v upper edge while the sidewall i8 has a pair of vertically faced bosses 32 extending inwardly from its upper edge.

Y Disposed between the sidewalls l? and i8 and secured to inner faces of the lugs 2| and 2,2 by

screws 38 and 39 is a frame plate 40. Secured to the lugs 28 against the lower and upper faces thereof by suitable screws are a cross-plate 4I and a horizontal deflection scale d2. Secured at its opposite ends to the bosses 29 of the sidewalls I1 and i8 is a control knob mounting plate 43. Held by suitable screws at its opposite edges to the Vertical lugs 24 and 25 at the fr-ont end of the housing I6 is a light screening plate lill.

The frame plate 4t has a universal pivot device 45 mounted on the inner face thereof near its lower edge by screws 46 extending through suitable apertures in said plate and into a U-shaped bearing 41 in the arms of which a shaft d8 journals.

Mounted on the shaft 48 is a block 49 which rotates freely between the arms of the U-bearing 41. Extending through said block and the shaft 48 at a mid-point in the latter is a shaft 50 which journals in the bifurcated arms of a U-bearing 5| which is secured by screws 52 to a reflector mounting plate 53.

The device 45 is mounted on frame plate 40 so that the point at which the axes of the shafts 4B and 5B intersect is located on what is designated herein as the reference axis of the headlight tester l5 (Fig. 2). Mounted in rubber spools G -secured to the plate 53 by screws 5l is a concave reector 52 (Figs. l and 5). The relation between the reflector 52 and plate 53 may be adjusted by tightening up or loosening one of the screws 6I which, through compressing the spool carried thereon, Varies the distance between the plate 53 and the portion of the periphery of the reflector 152` which is held by said spool.

Screwed into suitable tapped holes in the plate 45 are screws 65 of adjustable stops S5 and 51. The stop 66 is located in the Vertical plane containing the reference axis 55 (and above said axis) and. the stop E1 is located in the horizontal planer containing said axis and to the right of the latter. These stops are identical in structure so that a description of the stop will sufi-loe for both. The stop t6 includes one of the screws 65 having a lock nut 58 to nx this in any desired adjusted position in the plate fit. Screwed onto the screw 65 is a cylindrical nut 69, the threaded bore lil thereof having a counterbore 1l provided therein for receiving a contacter plug 'i2 which His' held in adjusted position in said counterbore by one or more Allen set screws 1S, of which there arc preferably three.

A radial hole 14 is provided in the cylindrical nut 89 for receiving a bight of a wire cable 15, this bight being made fast to said hole by a set screw 16 screwed into a suitable tapped hole in the nut 69 which opens into the hole 14.

The plate 53 has a hole 11 to which one end of a coil spring 18 attaches, the other end of said spring being -connected to a pulley mounting bracket 19 which is xed on the inner face of the frame plate 40 and which carries a freely rotatable sheave 80. The spring 18 thus holds thereflector mounting plate constantly in .contact with the contacter plugs l2, the purpose of which will be rnade clear hereinafter.

Also secured to the frame plate dii by the vscrew 38 and a screw di is a bracket 82 on which a sheave E3 is piv-otally mounted.

Fixed to the inner iace of the frame plate 4l) by the screw 3S and a screw 84 is a sheave bracket 85 pivotally carrying a sheave 36. Pivotally supported on suitable posts extending downwardly from opposite end portions of the cross-plate 4i are sheaves 8l and 88.

Pivoted on an angle bracket S9 mounted on the rooting 2E of sidewall it is a sheave 90.

The deiiection scale 42 has calibrations 95 pro,- vided thereon (Fig. l) which are numbered in opposite directions fram a central zero line 96 to indicate amounts of left or right deiection of. the reiiector 52 for a purpose which will be made clear later. f

Provided on the control knob mounting plate A3 are bearings @l in which shafts 98 freely rotate, these shafts having fixed thereto manual control knobs St and it, and cable drums HH and iti?. respectively.

Secured by suitable screws to the upper face `of lug 3l is an up-and-down deflection scale plate H33 while the saine screws secure a plate li'd to the bottom face of said lug. Provided on the plate w3 are calibrations Iilfl which are numbered serially in opposite directions from the zero line W to designate varying amounts of up or down deflection. Mounted rotatably on the Vlower face of the plate itt are sheaves IM and lili?. Mounted on the inner face of lug v2l of the wall .I8 is a bracket it@ carrying a rotatable sheave Hi).

Fixed on the bosses 32 are a lpair of angle brackets l it on which is mounted a rnilliammeter i i5 which operates in the invention as a candlepower meter and has a calibrated scale Ht and indicating needle lll as shown in Fig. 1.

rThe light screening plate 44 has a light sensitive cell H6, which is circular in character, mounted centrally thereon and concentrically with respect to the reference axis 55. The termi.- nals of the photo-responsive electric circuit in the cell H8 are connected by conductors ll'to the milliamrneter H5. Suitable light apertures E20 are formed in the plate 44 in symmetrical relation with the axis 55.

Also formed in the plate d4 near the lower edge thereof are sight holes l2! which are separated by a relatively thin front sight 22.

The cable 'l5 which, as previously described, is coiled about the nut 59 of the adjustable stop .66, is trained about pulley 83, from which vit extends to control drum id about which it is wound several turns and from which it passes over pulley lill, around pulley ille, and then around pulley et, from which the cable returns to the adjustable stop St. rlhe free kends of this cable are disposed between pulleys E6 and m3 and arejoined yby a tension spring l23.

Secured to the cable between the pulleys lill and Hi8 is a gib lZ which slides along an ad- 'jacent edge of the plate HB6, there being a ylinger 25 mounted on this gib which extends up therefrom and thenvhorizontally to overlie the up-anddown scale plate 103.

Thus it will be seen that by rotation of the control knob 99, the drum ll is rotated which causes rotation of the nut 69 of adjustable stop GB through the connection therewith of the cable l5. Rotation of 'this nut changes ythe distance which the 'forward tip of the contacter 'l2 of this `stop is located from the platev dt and causes a change in the vertical deflection of the reilector V62 from the position in which the reference axis 55 is normal to this reflector.

In a like manner, the adjustable stop 5l is conn trolled by manipulation of the control knob IGS through a cable i3d which winds about the nut 69 of .said stop.,v about the drurn EQ2 of the control knob l, is trained about sheaves dil, 3l, t3, 96, and itil, and has a contractile coiled spring .13% connecting its free ends to maintain it under tension. Fixed to the'cable I3@ at a point between sheaves Sl and 88 is a gib 532 which slides along the inner edge of plate il and has a nger 133 which extends upwardly around a corresponding edge or the scale plate d2 so as to overlie this plate and indicate thereon the amount oi deflection of the reflector t2 to the left or right of the vertical plane containing the axis d.

The cover 2! is in the shape of an inverted U and includes a top wall lill?, a front end wall H5! and a rear end wall i632. The top wall lli@ is apertured to receive the shafts t3 and to permit the candlepower meter H5 to extend upwardly therethrough.

It also has windows its and Mid through which the calibrations and ldd may be viewed. A sight well M5 is provided to permit the operator to look downwardly and forwardly at the screening plate M and the light sensitive cell lfl mounted thereon during the operation of the apparatus.

IThe front wall ilil is provided with a glass -window Mii through which light is admitted to the light apertures l2@ and lEl. The cover 2S is held in place by screws ldl which pass through suitable holes formed in front and end walls iti and id? and into suitable threaded `apertures provided in the sidewall lugs 23 and 25 respectively.

The end wall it?. has a sight hole it@ which lies in the vertical plane containing the axis and the front sight 22.

The bottom wall it of the housing it is secured by screws il to the ootings 2t and El. Secured as by screws idg to the upper race of the door lil just in front of the sight hole is a rear sight 53 having a notch 551i formed therein which lies in the vertical plane containing ie axis |The headlight tester i5 is supported on an ele vator platform Idil which is vertically slidable on tubular standards it! which are at their lower ends on a wheeled carriage M32, the latter having suitable flanged wheels (not shown) which travel on arpair of parallel tracks ITwo of these wheels travel on one of the tracks lii and a third, which is vertically adjustable by a screw 154i travels on the other of said rails.

The upper ends of the standards it! are connected by a headp-iece The platform 'itt includes a cross-head 155 having bearings itl and its which slide on standards I6 I. The cross-head ist includes two hollow boxes itt and Vid which are connected by spaced vertical walls lll and llt. rfhe cross-head lit and platform ltd are preferably integral.

As shown in Fig. l0,V platform itt' comprises an open rectangular traine V55 includes a boss H6 through which a screw i'i'l entends into the oor I9 to pivotally connect the headlight tester I5 to the platform Idd. y

The platform ld also has bosses llt* on which sleeves Ilii are pivotally mounted. Extending downwardly from the door i9 is a post Het. Journalled in suitable bearings provided in the crosshead walls lll and l'l2 is a control shaft [3l a manual control lever |52.

ylever has a cross pin |93 and extends into a notch 'aecomo having a knurled knob |82 fixed on its outer end and a spool |83 iixed on its inner end. Wound about spool |83 and trained about the sheaves |19 is a cable |845 having a spring |85 therein, opposite ends of which cable and spring are connected to the post |86.

Mounted in cross-head box |69 is a manually operated elevator clutch |88 including a vertically apertured plate |89 through which the adjacent tube standard El extends, there being coiled springs |96 coiled about said tube between said bar and the upper and lower walls of said box.

Extending through a slotv in the rear wall of box |89 and pivoted on a lug |t| formed on said box is The inner end of said |94 formed in the plate |88, the opposite ends of the pin |23 extending into horizontal slots |95 formed in said plate on opposite sides of said notch.

The clutch |88 oliers a means for making fine adjustments in the vertical position of the tester head on the tubular standards |6l, as described in U. S. Letters Patent to Holmes, No. 2,358,010.

The weight of the cross-head |65 and headlight tester i5 is ccunterbalanced in a manner well known in the art and therefore the means for this is not shown in detail in the drawings. This includes a steel strap its, one end of which connects to the cross-head |65 and the other end of which extends upwardly over a pulley in the head-piece |65 and down one of theA tubular standards ||i| where it connects with a counterbalance weight.

The manner of employing the headlight tester i5 in testing the headlights of an automobile is illustrated in Fig. 13. This is a plan View of an automobile 2li!) having headlights 22| and 2632, a radiator ornament 203 and a windshield 254 with a central molding 205.

When installing the tracks |63 these are placed with their upper edges parallel with the iioor on which they are mounted. The screw |64 is then adjusted to bring the platform i6() into parallelism f with the floor which is necessary for the proper functioning of the headlight tester I5.

To test the headlights 29| and 252, the automobile 280 is placed with its longitudinal axis perpendicular to the tracks |53 and with the lens of either of the headlights 29| or 202 approximately fourteen inches from the front of the headlight tester when the latter is located in alignment with said headlight. To obtain maximum accuracy the car 2li!! is rocked to relieve spring tension, and thev tires thereof are inflated to the proper pressure.

vThe tester is now moved to the center of the car and the operator looks through the rear sight |53, past the front sight |22 until he locates the reference axis 55 of the headlight tester in the same vertical plane with the longitudinal axis of the car 253|? as by sighting on the radiator ornament 203' and the central windshield molding 235.

Adjustment of the headlight tester |5 to thusVK platform |60 is now lowered until the tester is approximately in line with the headlight beam.

The knobs 99 and .|50 are turned to bring the fingers |25 and |33 opposite the zero marks |05 and 95 respectively. This brings the axis of the reiiector 62 into coincidence with the reference axis 55. Now, While Watching the candle-power meter H5, roll the tester back and forth along the track to the position where the maximum reading is obtained.V This having been done, the lever I 22 is manipulated to move the headlight tester up or down to the position where the candle-power meter shows a maximum reading.

The next step is tc rotate the knob 99 until the maximum reading appears on the candle-power meter i i5. Then rotate knob Ili until a maximum reading is obtained on the candle-power meter.

These steps are followed by a repetition of the steps of shifting the carriage |52 on the tracks v|63 until the maximum candle-power reading is obtainedand readjusting the platform |69 vertically until a maximum candle-power reading is obtained.

The readings on the scales 42 and I 93 now show the horizontal and vertical deflection of the headlight beam from horizontal-straight-ahead in terms of inches deflection at twenty-five feet, and the candle-power meter H5 indicates the actual candle-power output.

After determining and noting the present aim of the beam of a headlight, it is desirable to adjust the headlight so that the beam will be correctly directed therefrom. This is accomplished by turning the knobs 99 and 06 to set the lingers |25 and |33 at the proper values of vertical and horizontal deflection which the light beam is legally required to have. In nearly all States this is three inches below horizontal for the vertical aim and straight ahead for the sidewise aim.

The tester I5 having been set as indicated, the candle-power meter H5 will now give the maximum reading when the headlight has been adjusted so that the beam thereof is directed in accordance with the setting of the tester. The headlight is therefore now adjusted horizontally until a maximum reading appears on the candle-power meter and then vertically until a maximum reading appears on that meter. The adjustment of one headlight having been completed, the other light is adjusted in a similar manner.

The present invention supcrceeds a similar testerin Which the reflector 'was iixed within the housing and it was necessary to shift the axis of the entire housing vertically and horizontally in the process of measuring the precise direction in which a beam emitted by a given headlight is traveling. The mounting of the reflector in the present invention so that it may be readily rocked in vertical and horizontal planes about a point on the axis of the light cell which is located on the convex side of the reflector, greatly simplifies and lowers the cost of the tester and the mounting therefor.

The claims are:

l. In a Aheadlight tester, the combination of: a housing forming a chamber, said housing having a front wall with openings for the admission of light into said chamber; a light sensitive cell mounted on said front wall to face inwardly and having its axis coincident with and in fixed relation to a predetermined reference axis of the tester; a concave focusing reflector disposed at the opposite end of said chamber from said cell; a mount supporting said reflector for universal movement relative to said cell and having'the pivot point thereof coincident with and in fixed relation to said reference axis; manually operable means for controlling the universal movement of said reflector about said pivot point; and a candle-power meter operatively connected with and responsive to said light sensitive cell for measuring the intensity or" the light reiected onto said cell by said reflector.

2. A combination as in claim l in which said reiiectoy is mounted on a plate and said plate is in turn secured to pivotal mount; a pair of extensible stops provided on said housing to the rear of said plate and extending horizontally into contact therewith, one of said stops lying in a longitudinal. vertical plane containing said pivotal point, and the other of said stops lying in the horizontal plane containing said point; a spring holding said plato yieldably in contact with said stops; and mechanism connecting each of said controls to one of said stops for selectively extending or retracting said extensible stops for the purpose of rotating said reflector about said point in a vertical or horizontal piane as desired.

3. A combination in claim 2 in which each of said stops includes a screw mounted on said housing andV a nut into which said screw is threaded; and in said mechanism for rotating said nuts of said stops for controllably rotating said reflector about said point as aforesaid.

fi. A combination as in claim 3 in which rotation of said nuts is accomplished by cables Wound thereabout and rotary drums about which said cables are also Wound and which are provided with knobs disposed outside of said housing and the manual rotation of which is transmitted by said cables to said nuts.

5. A combination as in claim 4 in which graduated scales are provided on said housing and which are visible from, the exterior thereof, one of said scales being associated with each of said cables and having graduations, the scale associated With the cable connected With the nut of said stop in said vertical plane having graduations for measuring the tilt of said reflector in a vertical plane and the other of said scales being associated with the cable connected to the nut of the stop located in said horizontal plane and having graduations for measuring the tilt about said point of said renector in a horizontal plane; and fingers carried by said. cables and overlying the scales respectively associated with said cables, for indica-ting on said scales the precise amount of deviation of said reflector in a vertical or horizontal plane from a given reference position of said reiiector.

o'. in a headiight tester, the combination of: a housing forming a chamber, said housing having a front wail with openings for the admission of selected iight beams into said chamber, a light sensitive cell mounted in a forward portion of the chamber to face rearwardly and having its axis coincident with and in fixed relation to a predetermined reference axis of the tester, focusing reflector means disposed in a rearward portion of the chamber opposite said front Wall openings to face openings and said cell, said reflector means being mounted for universal tilting movement relatively to said celi and having the pivot point thereof coincident With and in fixed relation to said reference axis, manuallyT operable means lor controlling the universal tilting movement of said reflector means about said 'pivot point, means for indicating the degree of relative tilt of said reiiector means to said reference axis, and light intensity indicating means operatively connected with and responsive to said cell to measure and indicate the intensity of light reflected onto the cell by the reflecting means.

7. In a headlight tester, a housing forming a chamber and including a perforated front wall to admit-light to the interior of the chamber, a light sensitive cell mounted Within the chamber adjacent said front Wall and having its axis coincident vvith and in iixed relation to a predetermined reference axis of the tester, a reiiector disposed at the opposite end of the chamber from the cell to reflect light toward the cell, a universal joint mounted Within said chamber rearwardly of said reflector to support the saine for universal movement relatively to said cell and having the pivot point thereof coincident with and iixed relation to said reference manually operable means for controlling the universal movement of said reflector about said pivot point, and means operatively associated with said cell to indicate the intensity of light directed toward the cell by said reflector.

8. ln a headlight tester, a housing forming a chamber and including a perforated front Wall to admit light to the interior of the chamber, a light sensitive cell mounted Within'the chamber adjacent said front Wall and having its axis coincident with and in fixed relation to a predetermined reference axis of the tester, a tiltable reflector mounting plate disposed at the opposite end of the chamber from the cell, a reflector adjustably mounted upon said plate to reflectv light toward the cell, a universal joint disposed Within said chamber rearwardly of said mounting plate to support the same and its correlated reflector for universal movement relatively to said cell and having the pivot point thereof coincident with and in xed relation to said reference axis7 manually operable means for controlling the universal movement of said mounting plate and reflector about said pivot point, and means operatively associated with said cell to indicate the intensity of light directed toward the cell by said reflector.

9. ln a headlight tester, a housing forming chamber and including a perforated front wall to admit light to the interior oi the chamber, a light sensitive cell mounted Within the chamber acent said front wall and having its axis coincident with and in fixed relation to a predetermined reference axis of the tester, a tiitabie concavo-convex reflector disposed at the opposite end of the chamber from the cell to reflect li ht toward the cell, a universal joint disposed with said chamber on the convex side of said reflector to support the same for universal. movement relatively to said cell and having the pivot point thereof coincident with and in fixed relation to said reference axis, manually operable means for controlling thev universal movement of said refiector about said pivot point, and means operetively associated with said cell to indicate the intensity of light directed toward the cell by said reflector.

JAMES P. CRU

References Cited in the file of this patent UNITED STATES PATENTS Number 

